1. Field of Use
Train derailments are a common and everyday occurrence, causing significant injury to persons and property. A common cause of derailments is a heavy moving train passing over a section of weakened or otherwise defective railroad track. The railroad tracks are commonly made of some form of carbon steel or other ferromagnetic material. Sections of rail are placed end to end and welded together to form a single, continuous rail. Each rail is also bolted or nailed on cross tie supports, i.e., railroad ties, providing support for the rails and maintaining the proper space between the separate but parallel rail tracks.
After time and use, various components of the railroad track begin to fail. The weakening of the rail track may continue and eventually result in a failure causing a railroad derailment. The weakening of the railroad track is evidenced by cracks forming within the steel rail or in the welded joints between separate rail sections. It is also evidenced by other deformations in the steel tracks. However, it is difficult to detect cracked or weakened rail sections prior to the occurrence of a derailment.
2. Description of Related Art
Current methods for the detection of cracks, defective welds or other anomalies in railroad tracks use Electro-magnetically generated acoustic pulses. These pulses travel to a crack and their reflection is detected by sensors placed close to the rail surface. See U.S. Pat. No. 5,760,307. Such methods are, however, slow and require the sensors to be in very close proximity to the rail surface, typically within fractions of an inch.
The invention subject of this application creates a completely new type of rail inspection device that can be installed on every locomotive. The subject invention can be used on a locomotive traveling at full speed of 80 plus miles per hour at a location 10 inches to 18 inches or more above the track surface. This device is completely enclosed in metal or other material to protect its sensors from high-speed debris impacts and elements of weather. The present invention can also be used in conjunction with Global Positioning Satellite (GPS) systems to catalogue the signature and location of each detected anomaly. Further, the energy requirements of the present invention can be on the order of tens of watts.